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| From | Dave Tian <dave.jing.tian@gmail.com> |
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| Subject | question on string object handling in Python 2.7.8 |
| Date | Tue, 23 Dec 2014 20:28:30 -0500 |
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Hi, There are 2 statements: A: a = ‘h’ B: b = ‘hh’ According to me understanding, A should be faster as characters would shortcut this 1-byte string ‘h’ without malloc; B should be slower than A as characters does not work for 2-byte string ‘hh’, which triggers the malloc. However, when I put A/B into a big loop and try to measure the performance using cProfile, B seems always faster than A. Testing code: for i in range(0, 100000000): a = ‘h’ #or b = ‘hh’ Testing cmd: python -m cProfile test.py So what is wrong here? B has one more malloc than A but is faster than B? Thanks, Dave
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question on string object handling in Python 2.7.8 Dave Tian <dave.jing.tian@gmail.com> - 2014-12-23 20:28 -0500
Re: question on string object handling in Python 2.7.8 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-12-24 22:22 +1100
Re: question on string object handling in Python 2.7.8 Ian Kelly <ian.g.kelly@gmail.com> - 2014-12-24 09:39 -0700
Re: question on string object handling in Python 2.7.8 Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-12-25 17:23 +1300
Re: question on string object handling in Python 2.7.8 Denis McMahon <denismfmcmahon@gmail.com> - 2014-12-25 16:34 +0000
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